1. Field of the Invention
The invention relates to a liquid-lubricated bearing that includes an outer ring, an inner ring, and rolling elements. The invention also relates to a vehicle pinion shaft support device that includes a pinion shaft, such as a differential gear unit, a transaxle unit, or a transfer case.
2. Description of the Related Art
A conventional liquid-lubricated bearing that supports a pinion shaft of a differential gear unit is described in Japanese Patent Application Publication No. 11-48805 (JP 11-48805 A). A large amount of oil is sealed in the differential gear unit to reliably prevent seizure of components. The liquid-lubricated bearing is supplied with the oil in a differential case, which is thrown upward by a ring gear of the differential gear unit and then flows through an oil introduction passage.
The liquid-lubricated bearing is provided in the differential gear unit in which a large amount of oil is present. Therefore, there is a possibility that an excessive amount of oil will be supplied to the liquid-lubricated bearing, which increases the stirring resistance, resulting in an increase in the rotary torque. This may increase the operating cost of the differential gear unit, resulting in poor fuel economy of a vehicle that includes the differential gear unit.